Images of well casings and other tubular drilling operation components, such as risers, may be constructed using waveform data acquired from transmitting and receiving ultrasound. In some systems, parameters such as the waveform acquisition time and sampling interval are fixed, resulting in either oversampling (for small objects) or undersampling (for large objects). Oversampling may produce in more data than is needed for complete coverage, while undersampling can lead to missed defects. Thus, a more flexible approach is needed to reduce inspection times, conserve the memory used to store acquired data, and still provide substantially complete coverage of the imaged object.